1. Field of the Invention
The invention relates to an electric connector making mechanical and electrical contact with a core wire of a cable, and further to a terminal included in the electric connector.
2. Description of the Related Art
A coaxial cable includes a central electrical conductor as a core wire, an internal electrical insulator covering therewith the central electrical conductor, and an external electrical conductor comprised of a mesh wire, for instance, and surrounding the internal electrical insulator. The central electrical conductor and the external electrical conductor act as wires through which electric signals are transmitted. As an electric connector to be electrically connected to such a coaxial cable, various electric connectors have been suggested as follows.
FIG. 12 illustrates a connector 1100 used for a coaxial cable, suggested in Japanese Patent Application Publication No. 2005-332632.
In the connector 1100, when a cover housing 1101 is coupled to a main housing 1102, an external insulative cover, an external electrical conductor, and an internal insulative cover of a coaxial cable 1105 are cut in this order by a blade 1104 arranged in a slot 1103 to thereby cause the blade 1104 to make contact with the internal electrical conductor. Concurrently, a ground contact 1106 formed at the cover housing 101 is caused to make contact with the external electrical conductor.
In the connector 1100, a compressive force generated when a pair of compressing parts 1107 formed at the cover housing 1101 compresses the coaxial cable 1105 onto an inclining cam surface 1108 is converted into a force by which the coaxial cable is pulled in opposite directions about the blade 1104. Thus, in such a condition that the blade 1104 is caused to make compressive contact with the internal electrical conductor of the coaxial cable 1105, the external electrical conductor is torn in opposite directions about a projection 1109 formed at the main housing 1102. The blade 1104 is prevented from making contact with the external electrical conductor, because the projection 1109 acts as a wall. Thus, it is possible to cause the blade 1104 to surely make contact only with the internal electrical conductor.
FIGS. 13A to 13D illustrate a contact 1000 to which a cable is connected, as suggested in Japanese Patent Application Publication No. 2007-48696.
The contact 1000 has a V-shaped slit 1001 (see FIG. 13A). Portions defining the V-shaped slit 1001 or located sandwiching the V-shaped slit 1001 are used as compression terminals 1002. A punch 1004 formed with wavy grooves 1003 is compressed onto the contact 1000 to thereby collapse the portions towards the slit 1001, as illustrated in FIG. 13C, resulting in that core wires (central electrical conductors) 1006 of a cable 1005 are sandwiched between the portions.
FIGS. 14A to 14C illustrate a contact 1008 to which a cable is connected, as suggested in Japanese Patent Application Publication No. 2007-48696, as another embodiment.
In the illustrated embodiment, one of the compression terminals 1007A is bent towards the other compression terminal 1007B, and the compression terminal 1007B is bent towards the compression terminal 1007A such that their distal ends do not interfere with each other. Thus, the contact 1008 is completed.
In the connector 1100 illustrated in FIG. 12, an external insulative cover, an external electrical conductor, and an internal insulative cover of the coaxial cable 1105 are cut in this order by the blade 1104 to thereby cause the blade 1004 to make contact with the internal electrical conductor. Accordingly, when the cover housing 1101 is coupled to the main housing 1102, the internal electrical conductor may be accidentally damaged or cut by the blade 1104. In particular, since a recent coaxial cable is designed to have a small diameter, if the internal electrical conductor were damaged or cut, the reliability to electrical contact between the coaxial cable 1105 and the connector 1100 would be deteriorated. Furthermore, if the internal insulative cover were adhered to the blade 1104 and were put into the internal electrical conductor together with the blade 1104 when the internal insulative cover is cut by the blade 1104, a defect in the electrical connection would be caused.
For the purpose of avoiding the above-mentioned problem, the contact 1000 illustrated in FIGS. 13A to 13D is designed to make electrical contact with the central electrical conductors 1006 arranged naked by peeling off the external and internal insulative covers. In the contact 1000, the central electrical conductors 1006 are sandwiched in the slit 1001 by closing the V-shaped slit 1001 to thereby cause the contact 1000 and the cable 1005 to make compressive contact with each other. Thus, if the central electrical conductors 1006 are comprised of a bundle of thin wires, the thin wires could not be kept bundled, resulting in deterioration in reliability to the electrical connection between the cable 1005 and the contact 1000.
The contact 1008 illustrated in FIGS. 14A to 14C provides an advantage that since the compression terminals 1007A and 1007B are bent such that their distal ends do not interfere with each other, a space in which the central electrical conductors are housed can have a small diameter, ensuring that the central electrical conductors can be surely kept in the space. However, when the slit 1009 is closed, the compression terminals 1007A and 1007B exert a shearing stress on the central electrical conductors, as if something is cut by a pair of scissors, resulting in that the central electrical conductors may be accidentally cut by the compression terminals 1007A and 1007B.